This invention relates to a heat exchanger to be used for a refrigerating apparatus.
As the above-mentioned sort of heat exchanger, there has so far been known such one as shown in FIGS. 1 to 3.
The heat exchanging apparatus shown in these figures of drawing is of such a construction that a pair of heat exchangers 1, each being in a planar shape and made up of plates fins and heat transfer tubes orthogonally intersecting with the plate fins, are fixedly secured on an under-frame 3 and disposed in such a manner that an air blower 2 may be interposed between these two planar heat exchangers, and that both sides of the mutually opposed heat exchangers 1, 1 are closed by side plates 4, 5 to form a casing. The air blower 2 is fixed on a structure which projects upwardly of the under-frame 3. the top plate 6 for the casing is so provided that it may block flow of air in the casing together with the side plates 4, 5, thereby constructing the floor-setting type heat exchanging apparatus with good installing property. Further, a power source tap 7 is incorporated in an electrical circit of a refrigerating apparatus, and connecting tubes 8, 8 are joined with refrigerant circulating tubes in a refrigerant circuit shown in FIG. 4.
FIG. 4 is a schematic diagram showing a coolant circulating system of the refrigerating apparatus, in which the above-described heat exchanger is used. It should be noted that, in FIG. 4, the same component parts as those in FIG. 1 to 3 are designated by the same reference numerals. Besides these common constituent parts, a reference numeral 9 designates a refrigerant compressor, a numeral 10 refers to a water-side heat exchanger, a reference numeral 11 represents an expansion valve, 12 a gas-side four-way valve, 13 a liquid-side four-way valve, 14 an accumulator, and 15 is a refrigerant distributing tube, to which the connecting tubes of the heat exhanging apparatus is connected.
The refrigerant circuit shown in FIG. 4 is used in a case where the heat exchanger is to be operated as an evaporator, hence the following explanations will be made as to the use of the heat exchanger in such case. The refrigerating gas which has been compressed in the refrigerant compressor 9 is rendered a high temperature and high pressure gas, and flows into the water-side heat exchanger 10 through the gas-side four-way valve 12. In this heat exchanger 10, the refrigerating gas carries out heat-exchange with water to become condensed, i.e., it is turned into a high pressure refrigerant liquid. The high pressure refrigerant liquid passes through the liquid-side four-way valve 13 and is reduced its pressure by the expansion valve 11 to be turned into a low pressure refrigerant liquid, after which it flows into the heat exchanger 1 to perform the evaporating function. By the way, since the heat exchanger 1 is frosted by the evaporating function during the winter season, water draining takes place at the time of defrosting, and, during the intermediate seasons such as spring and autumn, no frosting occurs but dew condensation takes place on the heat exchanger, which also brings about draining of water.
The conventional heat exchanging apparatus of the above-described construction as shown in FIGS. 1 to 3 has various problems such that it requires a large number of component parts including a pair of heat exchangers and two side plates for the casing, and sufficient heat-exchanging space at both sides of the heat exchangers, and, more over, there are many restrictions imposed on its installation, by which the heat exchanging apparatus is limited to the floor-setting type, all these leading to the increase in cost for manufacture and installation of the heat exchanging apparatus.